Snail Shell Box

Ok I Bet This Topic Came Up Before But I Need You Guys Help. I Have A 95 Astro Van And I Have 2 Mtx 9500 10's And A Memphis Mojo Amp. How Well Do Those Snail Shells Work From Power 4 Sound Shop In Cali. To Tell You A Little About Me I Listen To Only Rap So I Love That Deep Hard Bass With That Pressure On My Chest. Is That The Box I Need The Double Shot Snail Shell Box? Thanks For Your Help Fellas